Construction of die-cast cylinder blocks



June 15, 1954 'v. BOGHOSSIAN 2,681,054

UQNSTRUCTION OF DIE-CAST CYLINDER BLOCKS Filed April 6, 1951 3 sheets sheet 1 I j INVENTOR.

V. BOGHOSSIAN CONSTRUCTION OF DIE-CAST CYLINDER BLOCKS June 15, 1954 3 Sheets-Sheet 2 Filed April 6, 1951 INVENTOR. l z'fo 7' flo a es 671471, BY 5 June 15, 1954 v. BOGHOSSIAN CONSTRUCTION OF DIE-CAST CYLINDER BLOCKS 3 Sheets-Sheet 3 INVENTORI. W'ciar fio /mssz'arz BY Filed April 6, 1951 Patented June 15, 1954 UNITED STATES TENT OFFICE CONSTRUCTION OF DIE-CAST CYLINDER BLOCKS Victor Boghossian, Ypsilanti, Mich., assignor to Kaiser Motors Corporation, a corporation of Nevada 12 Claims.

This invention relates to cylinder blocks for internal combustion engines, and more particularly to a construction whereby such cylinder blocks may be efficiently fabricated of aluminum, magnesium or other metals suitable for die-casting, and may be made using conventional die-casting techniques.

In the past it has been customary to fabricate the cylinder blocks of internal combustion engines by sand casting or permanent mold methods, a process which is relatively slow and expensive. E'he primary reason why this type of casting has been used rather than the more highly efficient die-casting process, is that the problem of coring the cylinder block has not permitted the use of the latter technique. In order to form the water jacket, crankcase cavity and other internal cavities of the cylinder block it has been necessary in the past to rely on retractive cores, or cores having removable parts. This has prevented the application of die-casting techniques to the formation of the cylinder blocks, since the high pressures involved in the die-casting process do not permit split cores or cores having relatively sliding parts.

It is therefore an object of this invention to provide a novel and improved construction for the formation of cylinder blocks by die-casting, without the necessity of using retractive cores or additional parts, but in which the entire interior or" the block maybe formed by two oppositely disposed and relatively movable cores, each of onepiece construction.

It is another object to provide an improved construction for cylinder blocks having the above characteristics, and in which the Water jacket core can be extracted from the block without the necessity of retractive cores or additional par-ts. In particular, it is an object to rovide such a construction which is adapted to be used in com junction with a wet sleeve type of cylinder, and in which the sleeve seat and the water jacket can be formed by two oppositely disposed relatively movable one-piece cores.

It is a further object to provide a. die-casting construction for cylinder blocks of the above character, and which is also provided with a novel transverse web construction in the vicinity of the crankcase cavity, which results in a much lighter construction without sacrificing rigidity.

It is also an object, in one form of my invention, to provide a method and construction by which cylinder blocks may be die-cast, in which the block is fabricated in two separately die-cast units, the first being a main block unit in which the camshaft bearings and tappet bosses are eliminated, and the second being a, longitudinal member of lighter construction which forms a side cover plate on the main block unit, and which includes the camshaft bearings, tappet bosses, and other auxiliary engine equipment.

It is another object to provide a two-section die-cast cylinder block construction of the above character, in which the primary block unit may be constructed as a load carrying structure, in which the side cover unit may have assembled thereto several of the auxiliary engine elements, and in which the units cooperate to provide a longitudinal oil gallery which may be partially cooled by the circulating water in the cylinder jacket.

Other objects, features, and advantages of the present invention will become apparent from the subsequent description taken in conjunction with the accompanying drawings.

In the drawings:

Figure 1 is an exploded perspective view, in cross-section, showing the main unit and side unit of a preferred form of die-cast cylinder block construction.

Figure 2 is a fragmentary side cross-sectional view showing the main unit and side unit in assembled relation.

igure 3 is a side elevational view, partly in cross-section along the line 3-3 of Figure 2, and showing the configuration of one side wall of the main section, as well as the shape of the crankshaft bearing webs.

Figure 4 is a fragmentary cross-sectional view taken along the line 44 of Figure 5 and showing the double wall construction of the crankshaft bearing webs.

Figure 5 is a sectional view in perspective taken along the line 55 of Figure '1 and showing the oil passage locations in the main unit.

Figure 6 is a cross-sectional View of a modified form of die-cast cylinder block construction, taken through a sleeve supporting seat.

Figure '7 is a view similar to Figure 6 but taken between a pair of adjacent sleeve supporting seats; and

Figure 8 is a fragmentary cross-sectional view taken along the line 8-4! of Figure 6 and shoW- ing the web construction.

The principles of construction of this invention are shown as applied to a typical in-line arrangement of cylinders in an internal combustion engine, although it will be understood that these principles are equally applicable to other arrangements of cylinders and for either single or multiple cylinder constructions. In the preferred form of my invention shown in Figs. 1-5, the cylinder block is constructed of two separately fabricated units, a primary or main unit generally designated as i I and a secondary or side unit 52 which when in assembled position is held in flush relation with appropriate surfaces on one side 13 of the main unit. The main unit comprises side wall l3 and an oppositely disposed side wall is the upper or Water jacket portions of which extend in substantially parallel relation and are joined by a horizontal transverse web or water jacket floor I 5. The upper edges of side i3 and M are provided with gasket seats i6 and the side walls are connected at their opposite ends by a pair of end walls ll, one of which is shown in Fig. 1. The upper edges of these walls may therefore form a continuous seat for a head gasket (not shown) for the cylinder block, and the walls together form a water jacket space for the engine cylinders, as will be hereinafter described.

The water jacket floor I is provided with a plurality of circular openings, from which. extend upwardly a group of cylindrically shaped seats I8, the purpose of which is to support removable cylinder sleeves as is later described. It will be noted that the water jacket space l9 extends between the outer surfaces of the seats I8 and the inner surfaces of walls I3 and 14. Connecting webs 29 may be provided between adjacent portions of the seats 18 for purposes of design, and walls i 3 and l l may have a slight outward and upward taper (not visible in the figures). These walls also have a series of longitudinally spaced vertically extending ribs 2i, the upper ends of which are provided with bolt holes 22 for the cylinder head when the block is finally machined.

The seats 18 terminate at the lower surface of floor 15 and between each two adjacent seats and extending downwardly from floor i5 is a crankshaft bearing web which extends transversely between the lower outwardly flaring portions of side walls 13 and hi. As is best seen in Figures 4 and 5, each crankshaft bearing web comprises a solid central portion 23 which extends downwardly from floor 15, and a pair of closely adjacent parallel walls 25 on either side of the central portion, walls 2 1 thus forming a plurality of inwardly extending parallel recesses along the side walls It and I l. The upper half 25 of each crankshaft bearing is formed at the lower juncture of portions 23' and 2a, with sufficient solid metal left on either side of the bearing half to allow the tapping of bearing bolt holes 26. Further lightening of the webs may be accomplished by the provision of a plurality of elongated concave recesses 21 on opposite sides of the solid portions 23 of the crankshaft bearing Webs. As seen best in Figs. 3 and 4, these recesses preferably extend downwardly from the lower edges of the seats It and cooperate with the double-wall construction to minimize the amount of excess metal in the webs. The outwardly flared lower portions of side walls and i i are also preferably provided with longitudinal strengthening ribs 28 and bottom flange portions 29 which serve to connect with the crankcase pan (not shown). The upper portion of side wall is is further provided with a plurality of longitudinal bosses 35, 32 and 33 which, as will be later seen, cooperate with mating surfaces on the side section I2 of the cylinder block.

The side section I2, like the main section ll described above, is also fabricated of a material suitable for die-casting, and incorporates the camshaft bearings, tappet bosses and supporting elements for other engine accessories. As is best seen in Fig. l, the section I2 comprises a lower camshaft bearing portion 35 of substantial C-shape, surmounted by an oil gallery wall 35, a horizontal tappet boss supporting deck 36 and an upper cover plate portion 31. The camshaft bearing portion 34 has sealing surfaces 8% and 39 for engaging respectively the bosses 32 and 33 on the main section, and comprises further a plurality of longitudinally spaced webs ll! and 5| disposed transversely within the portion 3% and having sealing surfaces 42 engageable with corresponding surfaces 43 on the main section. In particular, alternate webs 4| may constitute supports for the camshaft bearings, the remaining webs 48 being merely provided with clearance apertures to allow the camshaft to pass therethrough. The oil gallery wall 35 is immediately above the camshaft bearing portion 36 and is recessed a short distance from the plane of surfaces 38 and 39, the upper edge of the wall being provided with a sealing surface 44 which mates with surface 3| on the main section. It will be seen, as shown in Fig. 2, that when these mating surfaces are in assembled relation, they will form an elongated oil gallery 45 of rectangular crosssection, which is in heat-exchange relation with the water jacket space l9 to afford partial cooling of the engine oil by the circulating water. A plurality of passageways 46 are preferably cast in as vertical recesses in surfaces 43, and short horizontal ports 41 may be formed in webs 5| leading from these passageways to lubricate the camshaft bearings. Passageways 48 may also be formed leading diagonally downwardly from passageways 46 through web portions 23 for lubricating the crankshaft bearings.

The tappet boss supporting deck 36 extends substantially horizontally outwardly from the upper portion of oil gallery wall 35 and substantially parallel to the upper portion of camshaft bearing portion 34. A plurality of tappet bores 29 extend substantially vertically between the camshaft portion and the deck 36, so that continuous passageways are formed between the space within the camshaft portion and the space above deck 36. Two bores are provided adjacent each sleeve seat l8, and these bores may therefore receive the valve tappets (not shown) when the engine is assembled and operate valve mechanisms located within the space 59 enclosed within cover plate portion 3'! and the upper portion of side wall l3. If it is desired to use hydraulic tappets in the engine, this may be done without special machining by casting in a series of short passageways 5! within the oil gallery wall 35, these passageways extending from the oil gallery 5 to each of the tappet bores 49. A distributor support 52 and an oil pump support 53 are also preferably cast integral with the side section l2, as shown in Fig. 2, these portions being disposed outwardly of the camshaft portion as. The upper edge of cover plate portion 3? is provided with a widened sealing surface 54 in the plane of sealing portion I6.

It will thus be seen that the main section II and the side section l2 of the block are each capable of being integrally die-cast without the use of retractable cores or cores having removable parts, and the two sections may thus be constructed of aluminum, magnesium, or other metals suitable for die-casting. In particular,

the water jacket l9 may be formed by a single core which is part of the upper member of the die and movable in the direction of the cylinder axis as represented by the arrow 55, this upper core also serving to form the lightening recesses 21. The crankcase portion, crankshaft bearings and crankshaft bearing webs may be formed by a single core which is part of the lower member of the die, movable in the direction shown by the arrow 56. These webs, and especially the double walls 2 described previously, are also formed by side cores which are part of the side members of the die and move in the directions of arrows 5'! and 58 respectively. The side section I2 may likewise be formed by die-casting with single member cores, the main machining operations required after the casting being only the boring of webs 4!. Stud bosses 59 are preferably provided along the lower edges of surfaces 3i and 33, and the studs which extend from these bosses when the main and side sections are assembled are received through ears 6% depending from surfaces 38 and 44 of the side section.

The resulting structure of the cylinder block eliminates excessive metal concentrations in the bearing areas, especially at the camshaft bearings, since the latter are located in the relatively light side section i2. The main section H is treated as a load-carrying structure designed for high structural rigidity, while the side section l2 can be regarded as a part subjected to smaller stresses, and therefore of lighter design. This side section I2, which takes the place of the usual side cover plate found in conventional engines, also may serve an a sub-assembly unit, carrying in addition to the camshaft and tappets, the distributor, the oil pump and oil pump drive shaft, fuel pump, oil filter, and other accessories which may either be part of the casting or attached to it. The provision of side section [2 has the further advantage of incorporating a great number of intricate and accurate machining operations in a smaller and more compact unit, thus allowing smaller machines and tools to be used, and also eliminates many drilling operations for oil circulation passages by providing cast-in passages such as 36, 47 and 5!. Machining or foundry defects occurring at the camshaft bearings or tappet bores will necessitate only the scrapping of the side section l2, rather than the complete cylinder block. Moreover, servicing and replacement of parts are greatly facilitated by the accessibilty and removability of side section 52 and its associated parts.

.When in its finally assembled condition, the engine is provided with a plurality of sleeves 61, shown in dot-dash lines in Figs. 1 and 2. These sleeves are disposed within the confines of water jacket l9, and serve as conventional removable wet sleeves known in engine construction. The shoulder 52 of each sleeve is supported upon the upper edge of its corresponding seat 18, and the lower portion 63 of the sleeve extends downwardly with a slip fit within the seat. The portion of the sleeve above the seat is therefore entirely surrounded by the water jacket space i9. It will be understood that although the die-casting principles of the invention are shown as embodied in a cylinder blocking using a wet sleeve construction, these principles are equally applicable to the die-casting of other types of cylinder blocks.

Figures 6 to 8 illustrate a modified form of cylinder block which also embodies the principles of the invention, but in which the entire block is cast as an integral unit, including the camshaft bearings and tappet bosses. In this embodiment, the block comprises side walls 6% and 65 corresponding to side Walls l3 and M of the first embodiment, and which form the water jacket space 66. The lower portion 5'! of side wall 65 is flared outwardly, and the lower portion 68 of side wall 64 is spaced outwardly and in substantially parallel relation with the upper portion, a tappet boss wall portion 69 being disposed between portions 64 and 68. The cylinder sleeve seats '50 are formed immediately below the water jacket floor H and extend downwardly therefrom a short distance into the lower portion of the block, shoulders 72 being provided for supporting the cylinder Wet sleeve 13 shown in dot dash lines. The crankcase bearing webs M are generally similar to those of the previous modification, the webs adjacent wall portion 531 being of double-wall construction as shown Figure 8. In particular, this portion of the web is formed of two closely adjacent parallel walls 15 and iii leaving a lightening space '1! therebetween. oppositely disposed concave recesses '18 may also be formed at the central portion of each web 74, the crankshaft bearing "it being formed immediately below these recessed por tions. The portion of web 14 in the vicinity of wall 68 includes the camshaft bearings BI, and for this purpose the web in the vicinity of the camshaft is of solid construction rather than of double-wall construction, although the portion 82 of the web below the crankshaft bearings may be recessed. Oil passageways 83 and 84 may be provided in the finished block leading from the oil gallery 85 to the crankshaft and camshaft bearings. The tappet bores t6 are formed immediately above the camshaft bearing portion of the web, leading upwardly to the floor 39, and a plurality of strengthening ribs 81 may be provided along wall 64. The cylinder head stud holes 88 may be located in the crankshaft bearing webs l4 if desired, in place of the stud bosses 2| of the previous embodiment.

It will thus be seen that in the modification of Figs. 6-8, the cylinder block may likewise be formed with cores having no retracting or movable parts, and that the cylinder block embodies also the camshaft bearings and tappet bosses.

While it will be apparent that the preferred embodiments of the invention herein disclosed are well, calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A cylinder block for an internal-combustion engine, comprising a water jacket portion having oppositely disposed side walls forming a cast water jacket, and a plurality of sleeve-like seats disposed between said walls and cast integrally with said water jacket portion, said seats being located at the door of said water jacket and being adapted to support a plurality of cylinder sleeves within said water jacket, the inner faces of said water jacket above said seats so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion.

2. A cylinder block for an interial-combustion en ine, comprising a water jacket portion having oppositely disposed side Walls forming a cast water jacket, a plurality of sleeve-like seats disposed between said walls and cast integrally with said water jacket portion, said seats being located at the floor of said water jacket, and being adapted to support a plurality of cylinder sleeves within said water jacket, the space above said seats and between said water jacket side walls being unobstructed, crankcase walls integrally cast with and extending away from said water jacket, and a plurality of crankshaft bearing webs integrally cast with and extending transversely between said crankcase walls, each of said webs comprising portions of double wall construction formed by recesses extedning inwardly from said crankcase Walls.

3. A cylinder block for an internal-combustion engine, comprising a pair of oppositely disposed side walls forming a cast water jacket, a plurality of sleeve-like seats disposed between said side walls and integrally cast therewith, said seats being disposed at the floor of said water jacket and being adapted to support cylinder sleeves within said water jacket, the space above said seats and between said water jacket side walls being unobstructed, a pair of oppositely disposed side wall portions cast integrally with and extending away from said water jacket, a plurality of transverse webs extending between said crankcase walls and integrally cast there-with, a crankshaft bearing portion at the outer edge of each of said webs, a plurality of r cesses formed in one of said crankcase walls, whereby said webs are of double wall construction on the side adjacent said one crankcase wall, the other side of each of said webs being at least partially of solid construction, cam shaft bearing portions formed in said solid portions of said web, and a plurality of tappet bores formed in said cylinder block at the juncture of said water jacket and one of said crankcase walls, said tappet bores being adjacent said cam shaft bearing portions.

4. In a cylinder block construction for an internal-combustion engine, a main section comprising side Walls forming a cast Water jacket therebetween, a plurality of annular seats cast integrally with the floor of said water jacket and disposed within the lateral confines of said side Walls, said seats being adapted to support cylinder sleeves within said water jacket, the inner surfaces of said Water jacket above said seats being so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion, crankcase walls extending away from said water jacket, a plurality of crankshaft bearing webs extending transversely between said crankcase walls; and a side section having a camshaft bearing portion therein, said main section and side section having corresponding mating surfaces, whereby said sections may be secured together.

5. A cylinder block having a main section and a side section which are separately cast, said main section comprising oppositely disposed side walls forming a water jacket therebetween, a plurality of annular seats in longitudinally spaced relation between said side walls, said seats being cast integrally with the floor of said water jacket and adapted to support cylinder sleeves within said water jacket, the inner surfaces of said water jacket above said seats being so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion, a pair of oppositely disposed crankcase walls, and a plurality of crankshaft bearing webs extending transversely between said crankcase walls; said side section comprising an elongated camshaft bearing portion of substantially C-shaped crosssection, and a plurality of longitudinally spaced camshaft bearings Within said camshaft bearing portion.

6. A cylinder block having a main section and a side section which are separately cast, said main section comprising oppositely disposed side walls forming a water jacket therebetween, a plurality of annular seats in longitudinally spaced relation between said side walls, said seats being cast integrally with the floor of said water jacket and adapted to support cylinder sleeves within said water jacket, the inner surfaces of said water jacket above said seats being so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion, a pair of oppositely disposed crankcase walls, and a plurality of crankshaft bearing webs extending transversely between said crankcase walls; said side section comprising an elongated camshaft bearing portion having longitudinally spaced camshaft bearings therein, and a plurality of tappet bores extending upwardly from said camshaft bearing portion.

7. The combination according to claim 6, said side section further comprising an elongated oil gallery portion adapted to lie adjacent one of said water jacket side walls when said main and side sections are in assembled relation.

8. A cylinder block having a main section and a side section which are separately cast, said main section comprising oppositely disposed side walls forming a water jacket therebetween, a plurality of annular seats in longitudinally spaced relation between said side walls, said seats being cast integrally with the floor of said water jacket and adapted to support cylinder sleeves within said water jacket, the inner surfaces of said water jacket above said seats being so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion, a pair of oppositely disposed crankcase walls, and a plurality of crankshaft bearing webs extending transversely between said crankcase walls; said side section comprising an elongated camshaft bearing portion having longitudinally spaced camshaft bearings therein, and an oil gallery portion extending parallel to said camshaft bearing portion, said oil gallery portion being adapted to cooperate with one side wall of said main section to form an oil gallery; said one side wall having a plurality of channels leading from said oil gallery toward said crankshaft bearing webs.

9. A cylinder block for an internal-combustion engine, comprising a pair of oppositely disposed side walls forming a water jacket, a plurality of annular seats at the inner end of said water jacket and disposed within the lateral confines of said side walls, said seats being adapted to support cylinder sleeves within said water jacket, a pair of oppositely disposed crankcase walls extending away from said water jacket, a plurality of transverse webs extending between said crankcase walls, said webs having portions adapted to form crankshaft bearings and camshaft bearings. and a plurality of tappet bores formed in said cylinder block at the juncture of said water jacket and one of said crankcase walls, said tappet bores being adjacent said camshaft bearing portions.

10. A cylinder block having a main section and a side section which are separately cast, said main section comprising oppositely disposed side walls forming a Water jacket therebetween, a plurality of annular seats in longitudinally spaced relation between said side walls, said seats being cast integrally with the floor of said water jacket and adapted to support cylinder sleeves within said water jacket, the inner surfaces of said water jacket above said seats being so formed as to permit the withdrawal of a mold therefrom in a direction away from said floor portion, a pair of oppositely disposed crankcase walls, and a plurality of crankshaft bearing webs extending transversely between said crankcase walls; said side section comprising an elongated camshaft bearing portion having longitudinally spaced camshaft bearings therein, and an oil gallery portion extending parallel to said camshaft bearing portion, said oil gallery portion being adapted to cooperate with one side wall of said main section to form an oil gallery; and a plurality of oil passages through said camshaft bearings for carrying oil from said oil gallery to the camshaft bearings.

11. The combination according to claim 10, said side section being further provided with a plurality of tappet bores extending from said camshaft bearing portion adjacent said oil gallery portion, and a plurality of passages leading from said oil gallery to said tappet bores.

12. A cylinder block adapted for die casting, comprising a water jacket portion having oppositely disposed side walls forming a cast water jacket, a plurality of sleeve-like seats disposed between said walls and cast integrally with the between said crankcase walls, each of said webs comprising portions of double wall construction formed by recesses extending inwardly from said crankcase walls, the surfaces of said webs in the vicinity of the bearings being so shaped as to permit a core to be withdrawn from between said crankcase walls.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,301,254 Gunn et a1 Apr. 22, 1919 1,331,420 Diamond Feb. 17, 1920 1,720,625 Chorlton July 9, 1929 1,761,872 Chorlton June 3, 1930 2,064,282 Wohanka Dec. 15, 1936 2,199,423 Taylor May 7, 1940 2,280,753 Essl Apr. 21, 1942 FOREIGN PATENTS Number Country Date 259,313 Great Britain Oct. 11, 1926 

